Benq Projector SP840 Manuel D’Utilisation

Positioning your projector

16

1.

Select your screen size.

2.

Refer to the table and find the closest match to your screen size in the left columns 

labelled 

. Using this value, look across this row to the right to find the 

corresponding average distance from screen value in the column labelled 

. 

This is the projection distance.

3.

On that same row, look across to the right column and make note of the 

 value. This will determine the final vertical offset placement of the 

projector in relation to the edge of the screen.

4.

The recommended position for the projector is aligned perpendicular to the horizontal 

center of the screen, at the distance from the screen determined in step 2 above, and 

offset by the value determined in step 3 above.

For example, if you are using a 120-inch screen, the average projection distance is 4646 mm 

and with a vertical offset of 448 mm. 
If you place the projector in a different position (to that recommended), you will have to tilt 

it down or up to center the image on the screen. In these situations, some image distortion 

will occur. Use the Keystone function to correct the distortion. See 

 for details.

This method can be used for situations where you have purchased this projector and would 

like to know what screen size will fit in your room.
The maximum screen size is limited by the physical space available in your room. 
1.

Measure the distance between the projector and where you want to position the 

screen. This is the projection distance.

2.

Refer to the table and find the closest match to your measurement in the average 

distance from screen column labelled 

. If the min and max values are 

available on the table, check that your measured distance is between the min and max 

distances listed on either side of the average distance value.

3.

Using this value, look across that row to the left to find the corresponding screen 

diagonal listed in that row. That is the projected image size of the projector at that 

projection distance.

4.

On that same row, look across to the right column and make note of the 

 value. This will determine the final placement of the screen in relation 

to the horizontal plane of the projector. 

For example, if your measured projection distance was 4.0 m (4000mm), the closest match 

in the 

 column is 3872 mm. Looking across this row shows that a 100-inch screen 

is required.